HIGH · 8.8

CVE-2026-54999

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.

Vulnerability Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.

CVSS Score

8.8

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH

Affected Products

VendorProductVersions
MicrosoftWindows 10 1607< 10.0.14393.9339
MicrosoftWindows 10 1809< 10.0.17763.9020
MicrosoftWindows 10 21H2< 10.0.19044.7548
MicrosoftWindows 10 22H2< 10.0.19045.7548
MicrosoftWindows 11 24H2< 10.0.26100.8875
MicrosoftWindows 11 25H2< 10.0.26200.8875
MicrosoftWindows 11 26H1< 10.0.28000.2525
MicrosoftWindows Server 2012-
MicrosoftWindows Server 2016< 10.0.14393.9339
MicrosoftWindows Server 2019< 10.0.17763.9020
MicrosoftWindows Server 2022< 10.0.20348.5386
MicrosoftWindows Server 2025< 10.0.26100.33158

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-54999?

CVE-2026-54999 is a vulnerability with a CVSS score of 8.8 (HIGH). Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.

How severe is CVE-2026-54999?

CVE-2026-54999 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-54999?

Check the references section above for vendor advisories and patch information. Affected products include: Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows 10 21H2, Microsoft Windows 10 22H2, Microsoft Windows 11 24H2.